My 2005 King Quad is bogging out and I can not figure out why? I have a hmf muffler and a epi clutch kit without the fuel control modual. When i have the throttle pinned is runs as if it is not getting any fuel. It boggs right down. Is this because of the less restrictive exhaust throws off the fuel mixture?

 

thats what it sounds like. be careful, if it gets too lean, you can do BIG harm to the engine.